Fox AJ. Socio-economic differences in mortality and morbidity. Scandinavian Journal Social Medicine 1990; 18 (1): 1-8.

In England and Wales interest in differences in health between different sectors of the community can be traced back to analyses of vital registration records in the 1840s. Increased attention in recent years to differences between socio-economic groups, in part in response to initiatives by the World Health Organisation, has again exposed the limitations of traditional data. National data on this topic are now based on the OPCS Longitudinal Study, a record linkage study as used in a number of countries. Such studies provide more reliable measures of differences, cover a wider range of social dimensions, and also allow different explanations of differences to be investigated. Analyses of differences in mortality are complemented by longitudinal analyses of differences in health and morbidity now deriving from other studies such as the birth cohort studies which provide a basis for investigating processes. The time is ripe for more effort to be put into international comparisons of differences.